NBC IS ORDERING MORE CHUCK, IT MAY REPLACE ONE OF THE FAILING JAY LENO HOURS.
From Hollywood Reporter


NBC is in talks with Warner Bros. to order additional episodes of
"Chuck" ...


The number being bandied about is six additional hours (on top of the
13 episodes already ordered)...


An agreement has not yet been confirmed by the network ...


This could mean the show will return early, though an open time slot
has not yet presented itself.The original plan was for "Chuck" to
return in March.